Phys.org reports on the possible discovery of a long-sought-after dark matter particle, the so-called sterile neutrino.
The space between galaxies is not empty. It is filled with hot intergalactic gas whose temperature is of order ten million kelvin, or even higher. The gas is enriched with heavy elements that escape from the galaxies and accumulate in the intracluster medium over billions of years of galactic and stellar evolution. These intracluster gas elements can be detected from their emission lines in X-ray, and include oxygen, neon, magnesium, silicon, sulfur, argon, calcium, iron, nickel, and even chromium and manganese.
The relative abundances of these elements contain valuable information on the rate of supernovae in the different types of galaxies in the clusters since supernovae make and/or disburse them into the gas. Therefore it came as something of a surprise when [Harvard-Smithsonian Center for Astrophysics] astronomers and their colleagues discovered a faint line corresponding to no known element.
The scientists propose a tantalizing suggestion: the line is the result of the decay of a putative, long-sought-after dark matter particle, the so-called sterile neutrino. It had been suggested that the hot X-ray emitting gas in a galaxy cluster might be a good place to look for dark matter signatures, and if the sterile neutrino result is confirmed it would mark a breakthrough in dark matter research (it is of course possible that it is a statistical or other error).
(Score: 2) by Dunbal on Friday August 15 2014, @04:43PM
Here be dragons!
(Score: 2) by FatPhil on Saturday August 16 2014, @09:28AM
Anyway, which subatomic particle is the dragon? Does it have a supersymmetrical partner, the "dragino"?
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 2) by bob_super on Friday August 15 2014, @05:46PM
> whose temperature is of order ten million kelvin
I'm sorry, I don't understand which SPF to put on, can you convert that into Celsius?
(Score: 2) by maxwell demon on Friday August 15 2014, @06:04PM
At that order of magnitude, Kelvin and Celsius are effectively equivalent.
The Tao of math: The numbers you can count are not the real numbers.
(Score: 3, Funny) by Theophrastus on Friday August 15 2014, @06:24PM
Leela: Fry, night lasts two weeks on the moon.
Moon Farmer: Yep, drops down to minus-173.
Fry: Celsius or Fahrenheit?
Moon Farmer: First one, then the other.
(from the very first episode i do believe (we're whalers on the moon we carry a harpoon...))
(Score: 3, Funny) by migz on Friday August 15 2014, @07:07PM
Reminds me of when my primary school teacher taught us about how to use brackets, and asked us to write an essay to see if we got it. She was somewhat perplexed that I nested them to 3 levels...a sure sign of things to come...
(Score: 2) by mrider on Friday August 15 2014, @08:47PM
Apparently there currently aren't any Lisp programmers with mod points, otherwise there would be some funny mods. :)
Doctor: "Do you hear voices?"
Me: "Only when my bluetooth is charged."
(Score: 2) by c0lo on Saturday August 16 2014, @12:23AM
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 3, Informative) by PinkyGigglebrain on Friday August 15 2014, @09:54PM
a degree Kelvin and degree Celsius are actually the same unit. Its just that 0 Kelvin is at Absolute Zero, the temp where atomic motion effectively stops, and 0 Celsius is where water freezes at sea level pressure.
So;
degrees Kelvin = degrees Celsius + 273
http://www.pa.msu.edu/sciencet/ask_st/012992.html [msu.edu]
"Beware those who would deny you Knowledge, For in their hearts they dream themselves your Master."
(Score: 3, Insightful) by Alfred on Friday August 15 2014, @06:06PM
It tells you the SPF when you get the tourist brochures from there.
More seriously, the conversion won't even register in the significant digits.
Now my question, if it really is millions of kelvins...wouldn't we be awash in a lot more cosmic energy than we are? Even if it is far away? There is an astronomical amount of space between galaxies that would be generating this.
(Score: 1) by tftp on Friday August 15 2014, @06:37PM
You are floating in space. You are shot at with billions of terawatt lasers (say, mounted on enemy starships.) None of the laser beams hit you. How much energy of those beams do you absorb?
(Score: 1, Interesting) by Anonymous Coward on Friday August 15 2014, @06:59PM
This gas is VERY dilute, there's like one atom per cubic meter.
The millions of kelvins figure means these atoms are moving very fast in all directions, but if you happen to be there you'll still freeze to death.
Anyway, that's intergalactic gas there talking about, we're happen to be inside a galaxy, inside a solar system even, it's a different neighborhood altogether.
(Score: 2, Interesting) by Delwin on Friday August 15 2014, @07:11PM
Actually you likely won't - at least not very fast. You'll lose heat from radiation but not convection. You would asphyxiate long before you froze.
That said there's really not much in the way of a lower limit on how much heat you'll lose from radiation so you will eventually freeze... it'll just take a while.
(Score: 0) by Anonymous Coward on Friday August 15 2014, @06:48PM
can you convert that into Celsius?
10,000,000 - 273.15 = 9,999,726.85
Your welcome :P
(Score: 2) by khchung on Saturday August 16 2014, @02:26AM
Too bad I have no mod points to mod you funny, it would be even more funny if you asked to convert that to Fahrenheit.
To the humor impaired: when talking about order of magnitude ("of order ten million kelvin"), a factor of 9/5 will not matter, nor a slight difference of mere 273. So no matter if you use Kelvin, Celsius, or Fahrenheit, it would still be "of order ten million".
(Score: 2) by PinkyGigglebrain on Friday August 15 2014, @10:23PM
a known atom in a state not expected. I remember reading that there was a bit of a stir up over the discovery of an unknown element in the suns corona, but it turned out to be something more mundane
"Unknown spectral lines emitted by the corona were similarly credited to a new element "coronium" until Edlen showed that they came from the familiar atoms of iron, nickel and calcium, after they had lost an appreciable number of electrons (e.g. 13 or 14 for iron). Such high levels of ionization require the atoms to be buffeted around by extremely high temperatures, around 1,000,000 C (1,800,000 F)."
http://www.phy6.org/Education/wcorona.html [phy6.org]
I'm willing to bet that the spectral line isn't related to dark mater, either an error in the data or something mundane like normal mater under weird conditions.
As for Dark Matter, I'm leaning more towards the answer being something that is going to blow the socks off the scientific community, a new understanding of how gravity works or something else requiring a minor/major overhaul of our view of how the Universe works.
I'm also hoping that the new understanding gets Humanity closer to FTL travel, but not too close, we still need to get our crap together before we spread out into the Universe like locusts. But it would be nice to die knowing that our descendents will see first hand the wonders that are out there.
"Beware those who would deny you Knowledge, For in their hearts they dream themselves your Master."
(Score: 2) by aristarchus on Saturday August 16 2014, @08:49AM
OK, have to admit they lost me at up and down quarks, but seriously, sterile neutrinos? What are the other kind? Fertile? Or are these the ones that impel upon the Quantum Vacuum? Curious minds want to know!